1. Radiation: Data
Huh ???
So … how do we make sense of this data table?

2. Radiation: Sifting Demo15
Imagine that we have a pile of golf balls, beans and BBS; and that there are a total of 15 particles.

3. Radiation: Sifting Demo15 12
Now suppose that I sift the pile through a coarse screen, and I end up with a pile of just 12 beans and BBs.

4. Radiation: Sifting Demo15 12 5
Then, I sift that pile through a fine screen to get just 5 BBs. How many of each particle did I have in the first place?

5. Radiation: Sifting Demo15 12 5
GOLF BALLS: Started with 15 total (no screen), but 12 of those were beans & BBs that made it through the coarse screen. So, only 3 were golf balls.
None
Coarse
Golf Balls

6. Radiation: Sifting Demo15 12 5
Then, if 12 beans & BBs made it throught the coarse screen, but only 5 BBs made it through the fine screen, there had to be 7 beans.
Coarse
Fine
Beans

7. Radiation: Sifting Demo15 12 5
Last, 5 BBs made it through the fine screen.
Fine
BBs

8. Radiation: Sifting Demo15 12 5
None -
Coarse = 3
Golf Balls
Fine 7
Beans 5
BBs
Summary: No screen – coarse screen = golf balls, …

9. Radiation: Shielding None - Paper = 2 Alphas Copper 4 Betas 1 Gamma
Similarly, different particles pass through the different shields: alphas are blocked by paper, but betas and gammas make it through. Only gammas get through copper. So, no shield counts – paper counts gives alphas, etc.
None -
Paper = 2
Alphas
Copper 4
Betas 1
Gamma

10. Radiation: Shielding None - Paper = ? Alphas Copper Betas Gamma
Example numbers: Calculate the results …
None -
Paper = ?
Alphas
Copper
Betas
Gamma

11. Radiation: Shielding None - Paper = 112 Alphas Copper 1951 Betas 57
Gammas

12. Radiation: Shielding None - Paper = ? Alphas Copper Betas Gammas
You will use your actual counts …
None -
Paper = ?
Alphas
Copper
Betas
Gammas

13. Radiation: Shielding
Calculate the percentage of counts as shown

14. Radiation: Shielding
But, which isotope has this assortment of particles? ?

15. Radiation: Shielding
Find best match in Isotope Table …